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		<p>
            <br />
            <i>Empty points </i>are data points that do not have Y values or have been 
            marked as empty. They are visually displayed in the chart area. Empty points are 
            not the same as missing data points, which&nbsp; refer to data points that are 
            missing in a data set.</p>
        <p>
            The following example shows that there is no data for Wednesday.
        </p>
        <p>
            <table id="Table1" border="0" cellpadding="1" cellspacing="1" width="500">
                <tr>
                    <td>
                        <img alt="Missing Data?" border="0" src="MissingPoints1.PNG" /><br />
                    </td>
                    <td valign="top">
&nbsp;
                        <br />
                        <table id="Table2" border="1" cellpadding="1" cellspacing="1" width="100%">
                            <tr>
                                <td align="middle" valign="center">
                                    <strong>X</strong></td>
                                <td align="middle" valign="center">
                                    <strong>Y</strong></td>
                            </tr>
                            <tr>
                                <td>
                                    Monday</td>
                                <td>
                                    978</td>
                            </tr>
                            <tr>
                                <td>
                                    Tuesday</td>
                                <td>
                                    345</td>
                            </tr>
                            <tr>
                                <td>
                                    Thursday</td>
                                <td>
                                    567</td>
                            </tr>
                            <tr>
                                <td height="21">
                                    Friday</td>
                                <td height="21">
                                    778</td>
                            </tr>
                            <tr>
                                <td>
                                    Saturday</td>
                                <td>
                                    46</td>
                            </tr>
                            <tr>
                                <td>
                                    Sunday</td>
                                <td>
                                    78</td>
                            </tr>
                        </table>
                    </td>
                </tr>
            </table>
        </p>
        <p>
            If the X values of the plotted series are indexed, then it is possible that the 
            missing data is can be overlooked by the chart reader (see the figure below).</p>
        <p>
            <img alt="Missing Data and Indexed Points" border="0" 
                src="MissingPoints2.PNG" /><br />
        </p>
        <p>
            In this case, use an empty point to clarify that a data point is missing. For 
            example:</p>
        <p>
            <img alt="Missing Data and Indexed Points" border="0" 
                src="MissingPoints3.PNG" /></p>
        <h3>
            Empty Points Usage</h3>
        <p>
            Use empty points to:</p>
        <ul>
            <li>Represent points with NULL values. </li>
            <li>Change the appearance of missing data points. </li>
            <li>Align two or more series. </li>
        </ul>
        <p>
            Empty data points can be added to a series using:
        </p>
        <ul>
            <li>The Empty property of each data point in a series. If Empty is set to <b>True</b>, 
                a point is marked as empty. </li>
            <li>Data binding to DBNull values.&nbsp;If a point is data bound to a DBNull value it 
                will be marked as empty.</li>
            <li>The InsertEmptyPoints method of the DataManipulator class, which checks for 
                missing data and inserts empty points into a series using intervals.</li>
        </ul>
        <h3>
            Empty Points Styles</h3>
        <p>
            Empty points can be displayed as a marker or a line that connect the nearest two 
            points. It can be displayed as an average of the adjacent points or as having a 
            value of zero (see the figure below).</p>
        <p>
            <img border="0" src="MissingPoints.png" /><br />
        </p>
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